Filter bracket for light meters



Aug, 13, 1940. e. BUCHHOLTZ FILTER BRACKET FOR LIGHT METERS Filed Jan.21, 1939 2 Sheets-Sheet l INVENTQR George 5a c'kolzz ATTORNEYAugo13,1940. QBU'CHHOLTZ 2,211,557

FILTER BRACKET FOR LIGHT METERS Filed Jan. 21, 1939 2 Sheets-Sheet 2INVENTOR Patented Aug. 13, 1940 V I UNITED STATES PATENT OFFICE FILTERBRACKET FOR. LIGHT METERS George Buchholtz, Guttenberg, N. J.ApplicationJanuary 21, 1939, Serial No. 252,126

1 Claim. (01. ass-81.5)

This invention relates to new and useful im- Fig. 6 is a horizontalsectional view of the provements in' an automatic filter exposurebracket per se. meter. Fig. 7 is a view similar to Fig. 3 butillustrating More specifically, the invention proposes the amodification of the invention. construction of an automatic filterexposure Fig. 8 is a horizontal sectional view taken on 5 metercharacterized by the provision of a bracket the line 8-4! of Fig. '7.for engagement upon a conventionally con- Fig. 9 is a perspective viewof the light shade structed light meter which is adapted to receive perse. and hold a light filter over the light entrance Fig. 10 is ahorizontal sectional viewtaken on 10 element of the meter, the lightfilter being the the line Iii-40 of Fig. 9 and illustrating the light 10same filter that is to be used in front of the shade in position upon abracket supported upon lens of the camera when taking a picture for givalight meter.

ing a reading taking into consideration the cor- Fig. 11 is a sideelevational view of the light rection factor of said light filter. shadein position upon the bracket.

Another object of this invention is the provi- Fig. 12 is a sideelevational view of the light 5 sion of clip portions formed on saidbracket in shade in position upon a camera. a manner to be extendedalong the top and sides Fig. 13 is a similar view to Fig. 3, butillustratof said light meter for holding said bracket in ing anotherform of the invention. position upon said meter. The automatic filterexposure meter, accord- Still further the invention proposes the proingto this invention, should be used in conjuncgo vision of flange portionsformed on said bracket tion with alight meter in having a light entrancefor engaging the sides and bottom of said light element It! formed inone face thereof. The filter to fixedly hold the same in position uponsaid construction of the light meter I0 is conventional bracket. and thedetails thereof will not be given in this Another object of thisinvention is the provispecification, except to say that the lightentrance 25 sion of leaf springs stamped from certain of said element I0is in the form of an opening having flanges and which are adapted toengage the face a glass i l extended thereacross and through of saidlight filter for forcing the same into face which the light is adaptedto pass for contactcontact with said bracket. ing the light sensitiveelements of the light meter 0 Another object of this invention is theprovifor giving the proper exposure readings for setting sion of acircular flange formed on said bracket the stop and time exposures of acamera. and upon which a light shade to be used over the A bracket forsupporting a light filter over the lens of said camera is adapted to beengaged for light entrance Ill of the exposure meter is producing thesame lighting conditions for takadapted to receive andhold the samelight filter ing the exposure reading as would be present. in which isadapted to be used in connection with 35 the camera at the time the filmis exposed. the lens of the camera for giving an exposure For furthercomprehension o the vent o reading taking into consideration thequalities and of the objects and advantages thereof, referof the filterto be used. ence will be had to the following description and Thebracket is constructed of seperate plates 40 accompanying drawings, andto the appended consisting of a back plate I2 and a front plate 4 claimsin which the various novel features of the i3. The back plate 12 isformed with an openinvention are more particularly set forth. ing l2 inalignment with the light entrance ele- In the accompanying drawingsforming a mament ill of the light meter I0. The back plate terial partof this disclosure: I2 is formed with a top rearwardly extending Fig.1,is a perspective view of the light meter clip portion l2 for engagingthe top of the light 45 to be used in conjunction with this invention.meter as shown in Figs. 2 and 3 for preventing Fig. 2 is a view similarto Fig. l and illustratthe bracket from slipping down upon the face ingthe bracket in position on the meter. of the meter anddisaligning theopening 42 with Fig. 3 is a view similar to'Fig. 2 and illustratthelight entrance element I0 50 ing the light filter in position upon thebracket. The adjacent faces of the plates I2 and i3 are Fig. 4 is a rearelevational view looking in the secured together by welding, brazing orin any direction of the line 44 of Fig. 2. other desired manner. Thesides of the front Fig. 5 is a plan view looking in the direction ofplate l3 are formed with rearwardly extending the line 55 of Fig. 3.clip portions It which are bent around the sides g of the rear plate I2and which are adapted to engage the sides of the light meter I0 forpreventing longitudinal movement of the bracket thereon and formaintaining the opening I2 in alignment with the light entrance elementof the meter I0. A felt sheet I4 is attached to the back face of therear plate I2 and is normally disposed between the adjacent faces of thelight meter I0 and the bracket for preventing the face of the lightmeter from being marred when the bracket is engaged thereon and forsealing the contacting faces of the meter and bracket for preventinglight from entering there-through and interfering with the correcttaking of an exposure reading.

The front plate I3 is formed with an enlarged square cutout, the edgesI3 of which are bent into receiving flange portions for supporting alight filter I5. The receiving flange portions I3 are so arranged as tobe capable of engaging the sides and bottom edge portions of the lightfilter I5 for holding the same in alignment with the opening I2 formedin the rear plate I2.

The operation of this form of the invention is as fol1ows:-

For taking an exposure reading which will take into consideration thedensity of the light filter to be used over the lens of the camera, thebracket is engaged on the face of the light meter III with the openingI2 of the bracket aligned with the light entrance element III of themeter. The light filter I5 which is to be used in connection with thelens of the camera is then engaged into the bracket by passing the samevertically downwards into the receiving flange portions I3 formed on thefront plate I3. The light then passes through the light filter I5contacting the light sensitive elements of the light meter for giving areading which will take into consideration the filter I5.

After the reading has been taken and the camera has been properly set inaccordance with the reading the light filter I5 is removed from thebracket and engaged into a conventional filter holder for holding thesame in position in front of the lens of the camera.

According to the modification of the invention shown in Figs. '7 and 8the constructon of the bracket for supporting/the light filter I5 is similar to that previously described except that the receiving flangeportions I3 are not .bent from the edges of the front plate I3 asdescribed in the previous form of the invention. Instead, the receivingflange portions I3 are formed by stamping lugs from the side and bottomportions of the front plate I3. The lugs are then bent into the propershape for receiving and holding the light filter I5 as shown in Fig. 7.A means is provided for forcing the light filter I5 in face contact withthe adjacent faces of the rear plate I2. This means comprises verticalleaf springs stamped from the side receiving flange portions I3 andwhich bear against the outer face of the light filter I5. These leafsprings I3 are stamped from the side receiving flange portions I3 insuch a manner that the top ends thereof are integral with the flanges,while the bottom ends thereof are free for resiliently forcing thefilter against the face of the plate I2 for preventing light frompassing between the adjacent faces of these members.

According to the modification of the invention shown in Figs. 9-12inclusive the construction of the bracket is such that the light shadeused in connection with a camera 20 may also be engaged on the lightmeter I I] in alignment with the light entrance element II'I for givingan exposure reading which takes into consideration the said light shade.

In this form of the invention the bracket is engaged upon the lightmeter I0 and the front plate I3" thereof is formed with a circularopening 13 which is in alignment with the opening I2 formed in the rearplate I2. The material of the front plate I3" around the edges of theopening I3 is extended forwards for forming a circular flange I3 uponwhich the light shade 2I is adapted to be engaged. The light shade 2| isconstructed of separate sections consisting of a rear section 2 I whichis adapted to be enga upon the lens of the camera 20 or upon the flangeI3 of the bracket. The light shade is further formed with a shadesection 2| which is adapted to be threadedly engaged into the section 2Ias shown in Fig. 10.

The section 2I is formed with an inwardly extending flange 2 I and thesection 2 I is formed with an inwardly extending flange ZI When theshade section 2 I is in position upon the rear section 2 I the flanges 2I and 2 I are normally spaced from each other for forming a space 22into which a light filter I5 of the desired density is adapted to beplaced.

A means is provided for holding the lightshade 2| in position uponeither the flange I3 of the bracket or the lens of the camera 20. Thismeans comprises a pair of outwardly curved spring members 23 which havetheir ends passing through elongated slots 24 formed in the rear section2i of the light shade 2|. the spring members 23 are securely attachedtogether and are mounted upon finger engaging elements 25. In engagingthe light shade on the flange I3 as shown in Fig. 10, or upon the lensof the camera 20, ones fingers are rested upon the finger engagingelements 25 and the same are manually pressed together for causing thesprings 23 to be urged apart to permit them to be engaged upon eitherthe flange I3 or the lens of the camera 20. The finger engaging portions25 are then released for permitting the springs 23 to snap back intoposition and tightly clamp the respective portion upon which the lightshade is being engaged. It is also possible to use the light filter I5without the shade section 2I by using a ring in place of the shadesection 2| for holding the light filter in position upon the rearsection 2I In other respects this form of the invention is similar tothe other forms.

In Fig, 13 the light filter holding plate I5 is shown to be attached toone face of the meter ID by screws I6 or the like, and edges I3 areadapted to receive a substantially rectangular light filter plate I5. Inother respects this form of the invention is similar to the previousforms.

While I have illustrated and described the preferred embodiments of myinvention, it is to be understood that I do not limit myself to theprecise constructions herein disclosed and the right is reserved to allchanges and modifications coming within the scope of the invention asdefined in the appended claim.

Having thus described my invention, what I claim as new, and desire tosecure by United States Letters Patent is:

A filter bracket for light meters and the like formed of sheet materialand comprising a generally rectangular rear member stamped from flatsheet material, having a central light aperture and a rearwardly flangedupper edge por- The ends of i tion for resting on the top of afightmeter, and a generally U-shaped front member also stamped from sheetmaterial and int rally secured to the front of said rear member, heinner edge portions of said front member forming L-shaped flangessurrounding three sides of said central light aperture whereby togrovide a frame support for a filter, said front member having a sidelug bent rearwardly from each vertical side edge portion thereof forgripping the sidestof the light meter.

GEORGE BUCHHOLTZ.

